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### Disk spinning at the speed of light [duplicate]

Of course, I mean that the edge of the disk is traveling at the speed of light. This is a question that popped into my head a few years ago when I was learning about some basic relativity in high ...
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### Paradox of the Relativistic Record Player [duplicate]

Possible Duplicate: Invariant spacetime - distance - Circular Motion This is a question that I thought up a few years ago when I was taking mechanics. I asked the professor but didn't really get ...
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### A question about the relativity of time [duplicate]

Possible Duplicate: Invariant spacetime - distance - Circular Motion I understand that the closer something travels to the speed of light, that time will stretch by a factor, and distance will ...
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### Euclidean geometry in non-inertial frame

Refer, "The classical theory of Fields" by Landau&Lifshitz (Chap 3). Consider a disk of radius R, then circumference is $2 \pi R$. Now, make this disk rotate at velocity of the order of c(speed of ...
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### Circumference of a circle in a co-rotating frame of reference

According to Einstein it should be greater than $2 \pi R$ for a co-rotating observer, i.e. $L' = \gamma L$ where $L = 2 \pi R$ in a non-rotating frame and $\gamma$ is the usual Lorentz factor, which ...
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### Can rotating disk clocked at its center at the speed of light have an outer edge that travels faster than the speed of light? [duplicate]

I have been running this through my head for a few days and I understand I am probably missing something very simple here. If a wheel is spinning the outer edge will travel at a speed that is greater ...
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### Understanding the “$\pi$” of a rotating disk

Let us say you are in an inertial reference frame with a circular planar disk. If you take your meter measuring rods (or perhaps tape measure) you can find the diameter and circumference of the disk. ...
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### Speed greater than light in circular motion [duplicate]

We know that linear speed of object going around a circle is $\omega * r$ Now let us take an elastic string and rotate a body of negligible mass with $\omega = 500 rad/s$ It is possible to further ...
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### The relativistic effects of angular velocity

Imagine I have a circular disk in a vacuum. I apply a constant force, so a constant torque on the disk. My first question is: does this disk have a angular velocity speed limit? I believe it does, ...
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### How would be tv reception in a spaceship travelling close to speed of light?

My little brother has made me a tough question (specially for a computer science engineer). Imagine that there is a spaceship orbiting earth close at nearly speed of light (say 99%). Someone in earth ...
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### How does Lorentz Contraction apply to the edge of a spinning disk and is π still constant?

This may seem like a dumb question, as I'm not really a physicist, but here it goes. So, π is the number of diameter distances required to equal the circumference of a 2D disk. Relativity tells us ...
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### What is the relativistic mass of this spinning ball? [closed]

Relativistic Mass is: $$m_r = \frac{m}{\sqrt{1 - v^2/c^2}}$$ So Einstein says that the faster an object moves, the more mass it gains (relativistic mass). So suppose you have a spherical ball ...
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### What happens to a ball spinning with peripheral speed near to the speed of light?

I can't imagine such phenomenon. Would it becomes an ellipsoid, or maybe a straight line?